The screens which line water wells in one or more producing areas are subject to plugging by organic and inorganic materials, including micro-organisms and minerals such as iron, manganese, calcium and magnesium. The wells can also become plugged with fine particulate material from the surrounding formation. The gravel pack or other formation around the well is susceptible to becoming plugged by the same types of materials. The fractures of open hole rock wells also become plugged with the same types of materials. When the well becomes plugged, the flow of water into it is restricted, and the quality of the water can also suffer.
Various techniques have been proposed for cleaning the screens and surrounding gravel pack. For example, chemicals have been injected in order to chemically dissolve minerals and other materials. Mechanical agitators have been used to physically dislodge foreign materials from the screen. However, these approaches and other techniques that have been used have not been entirely effective in dealing with all of the problems of plugged wells.